1. Field of the Disclosure
The disclosure generally relates to materials and methods for the preparation of nanocomposites. More specifically, the disclosure relates to inorganic capped colloidal materials and the methods of depositing these inorganic capped colloidal materials on a substrate to form nanocomposites. Still more specifically, the disclosure relates to the selective deposition and formation of nanocomposites on a substrate.
2. Brief Description of Related Technology
Nanoscale materials, materials with at least one dimension between about 1 and 1000 nm, have increasingly garnered attention due to their potential electronic, photophysical, chemical, and medicinal effects. The large-scale industrial application of nanoscale materials has generally focused on the formation of nanometer thick films and/or nanometer wide wires. Many of these industrially-applied nanoscale materials display extraordinary electronic and photophysical properties, but more often the materials lack the features that originally drew scientific interest toward nanocrystals, nanorods, and nanowires.
Attempts to incorporate the physical properties of nanocrystals, nanorods, and nanowires into films or bulk solids have led to the self-assembly of ordered nanoarrays. These self-assembled ordered nanoarrays have been produced from stable colloidal solutions of nanomaterials. For example, close-packed nanocrystal films have been made by spin-coating or drop casting of colloidal solutions. Often these films show short range ordering, but forces such as entropy, electrostatics, and van der Waals interactions can cause these materials to self-assemble into superlattices. These techniques have afforded binary superlattices with tunable electronic structures based on the colloidal materials employed in the synthesis.
Though some single-component and binary superlattices exhibit desirable physical and electronic properties, these materials are not robust enough for large scale advanced material applications and their synthesis is not general enough to provide easy production of idealized materials.
A larger-scale approach to the synthesis of solid state materials encompassing nanocrystals is the impregnation and forced crystallization of nanocrystals from melts of inorganic materials. This rapid quenching approach can provide nanocrystalline material in bulk inorganic phases but lacks any methodology for the formation of ordered nanoarrays in the bulk material.
While the synthesis of solid state materials with ordered arrays of nanoscale materials has progressed to the point where nanocrystals can be deposited in ordered arrays on a surface, the use of these ordered arrays are hampered by the insulating ligands generally used in the manufacture of the nanocrystal. The practical use of these nanocrystals has been discovered through the blending of these organic soluble nanocrystals with polymers. See for example U.S. Pat. No. 7,457,508. For example, nanocomposites of nanocrystals and conjugated polymers can yield tunable semiconducting photonic structures, and with unique optical, electrical, magnetic, electrochromic, and chemical properties. See for example U.S. Pat. No. 7,200,318.
The majority of applications wherein these advanced materials would be applicable employ inorganic solids as the functional material. One example of an applicable inorganic solid that incorporates nanoscale materials is the fabrication of inorganic nanocomposites described in U.S. Pat. No. 7,517,718. This methodology involves the codeposition of a nanocrystalline material with an inorganic matrix precursor from a homogeneous hydrazine solution, a technique similar to the deposition of nanocrystalline materials in polymers as described in J. W. Lee et al., Advanced Materials 2000, 12, 1102. This methodology fails to provide the selectivity of structure for the synthesis of tunable semiconducting materials, does not prevent the carbon contamination of the synthesized inorganic nanocomposite, and requires a highly toxic, hypergolic solvent. Hence, the industrial applicability of the methodology is limited by material requirements, and the overwhelming health and safety concerns.
Examples of materials and devices applicable to the current invention are described in the following U.S. Pat. Nos. 6,571,028; 6,611,640; 6,710,911; 7,095,959; 6,697,548; 7,110,640; 7,200,302; 6,872,450; 7,192,780; 7,482,059; 7,399,429; 7,341,734; and 7,524,746; the following U.S. patent application Ser. Nos. 11/403,090; 11/484,785; 11/679,746; 11/680,047; 11/680,344; 11/683,880; 11/687,306; 11/747,701; 11/752,748; 11/863,129; 11/866,974; 11/896,549; 11/952,783; 12/048,061; 12/052,380; and 12/350,615; and the following International Patent Applications: PCT/2005/016481; PCT/2005/024131; PCT/2005/024211; PCT/2006/003652; PCT/2006/027124; PCT/2006/027125; PCT/2007/015851; PCT/2007/025235; PCT/2007/063788; PCT/2007/063788; PCT/2007/065951; PCT/2007/065951; PCT/2007/069572; PCT/2007/069572; PCT/2007/071218; PCT/2007/071218; PCT/2007/071218; PCT/2007/072748; PCT/2007/072761; PCT/2007/079688; PCT/2007/079688; PCT/2007/080436; PCT/2007/082066; PCT/2007/085824; PCT/2007/086480; PCT/2007/086819; PCT/2007/086819; PCT/2008/052620; PCT/2008/052620; PCT/2008/053651; PCT/2008/056845; PCT/2008/057681; PCT/2007/003525; PCT/2007/003411; PCT/2007/005589; PCT/2007/007424; PCT/2007/008705; PCT/2007/008721; PCT/2007/008873; PCT/2007/009255; PCT/2007/013152; PCT/2007/013761; PCT/2007/019797; PCT/2007/024305; PCT/2007/024306; PCT/2007/024310; PCT/2007/024312; PCT/2007/024750; PCT/2007/019796; PCT/2007/014705; PCT/2007/014711; PCT/2007/014706; PCT/2007/024320; PCT/2008/007902; PCT/2008/008036; PCT/2008/008822; PCT/2008/007901; PCT/2008/008924; PCT/2008/010651; PCT/2008/013504; PCT/2009/002123; PCT/2009/002796; PCT/2009/001372; PCT/2009/002789; PCT/2009/004345; and PCT/2009/004354; each of which are incorporated by reference herein in their entirety.